Tube shield



Sept. 16,1958 F. R, AMA 2,852,594

' TUBE SHIELD Filed May 22, 1956 TUBE H1ELD Frank R, Amend, Westmont, Ni 1., assignor to the United States of America as represented by the Secretary of the Air Force Application May 22, 1956, Serial No. 536,628

Claims. (Ci. 174--35) The present invention relates to an adjustable tube shield assembly to support and lock an electron discharge or vacuum tube Within its socket, and more particularly to an improved tube shield assembly for subminiature type tubes.

It is an object of the present invention to provide a tube shield assembly which is easily adjustable and removable yet will completely enclose and securely support a tube within its socket.

It is another object to provide a tube shield assembly having a minimum number of parts, yet conformable for use over a wide range of tube lengths and variations in nominal tube sizes.

It is another object to provide a base support assembly which will anchor the shield in position on the tube and will further lock the tube against release, and further provide a self-clamping shield and support assembly which will fit snugly around a miniature or subminiature type tube, is adjustable in length and diameter, and will establish a conductive heat path from the tube to the chassis.

It is still a further object to provide a shield assembly and base assembly which have mated louvered portions for air circulation, which are adjustable on one another, and may be interlocked to hold the tube in position.

To accomplish the foregoing general objects, and other more specific objects which will hereinafter appear, the present invention will be more fully understood by ref erence to the following detailed description and drawings in which:

Fig. l'is a side elevation of a tube shield and base support in assembled position on a tube;

Fig. 2 is a plan View showing the base support before bending into position;

Fig. 3 is a perspective view of the base support bent for positioning on the chassis;

Fig. 4 is a plan view showing the tube shield in open, unbent position;

Fig. 5 is a perspective view of the shield in bent position for clamping over the tube.

Referring more particularly to the drawings, there is shown in Fig. 1 a base plate or support bracket 10, and a tube shield 20 enclosing the base plate and tube 3%). The base plate 10 is made up of a bottom, horizontal portion 11 which is secured to the chassis 112 and an upright support portion or a standard which bears against one side of the tube 30. The shield 21 is broadly in the form of a cylindrical clamp or wrapper 28 so as to embrace and enclose the tube under spring action; it further includes a top contact portion 23 to fit across the top portion of the tube to thereby restrain the tube axially against movement.

In addition, both the standard portion 15 and clamp portion 23 are provided with mated holding means 18 and 26, respectively, which also act as ventilating portions to allow air circulation about the tube 30. It is to be noted that the outer clamp portion of wrapper 23 2,52,594 Patented Sept. 16, 1953 is provided with a greater number of holding means or louvers 26 than the standard portion 15; in this way, adjustment of the wrapper 28 onto standard 15 is possible to conform to the length of the tube 30.

As shown in Figs. 2 and 4, the entire assembly consists only of two parts, the support bracket 10 and shield assembly 20. Figs. 2 and 3 show the support bracket 10 having the horizontal portion 11 provided with holes 13 for securing the support bracket to the chassis and an enlarged opening 14 for placement of the tube 30 within its socket 31. The standard portion 15 is bent substantially vertically upward from the portion 11 and includes flaps or ribs 16 which are bent at right angles to louvered section 17 as shown in Fig. 3, in order to permit the passage of air through the louver members 18 and 26 and about the tube 30, and to stiffen the louvered section 17. In my preferred embodiment, the louvered section 17 is shown pierced with a series of four louvers 18 which preferably extend outwardly and downwardly from the surface of the standard and are closed at the top and open at the bottom, thereby encouraging upward circulation of cool air between the bracket and the tube. The louvers 18 are also preferably positioned on the lower part of the standard 15 in juxtaposed relation to the surface of the tube to further'encourage upward circulation 6f cool air about the tube. The support bracket 10, which is made of suitable resilient material, can be bent or formed so that the upright support portion 15 is substantially at right angles to the horizontal portion 11 and curved inwardly as shown at 19 to bear against the tube 30. Being resilient, the upright support portion or standard 15 may then adjust itself to accommodate variations in tube diameter. 5

The shield portion 20, shown in Figs. 4 and 5, is also I made of resilient material comprising the main wrapper or tubular clamp portion 28 having a middle tab or extension 21 at one side and two outer tabs or extensions 22 at the opposite side thereof. Extending above the clamp portion 28 is a top retainer plate 23 having a neck portion 24 and U-shaped head portion 25. The louvers 26 are vertically spaced intermediate the tabs 21 and 22 and directly below the top retainer plate 22, four to nine louvers being preferably pierced on the face of the clamp portion any four of which may be mated with those on the standard 15.

For assembly of the shield on the standard 15 and tube 30, the clamp portion 28 is bent to a substantially tubularconfiguration, the ends or tabs 21 and 22 being formed so as to intermesh and to apply equal and opposite forces against the opposite sides of the clamp 28, as shown in Fig. 5. The top retainer plate 23 is bent so that the head portion 25 will be positioned directly above the center of the tubular clamp, the neck portion remaining substantially upright. After fastening the support bracket to the chassis and inserting a desired tube 3d within its socket 31, the shield 20 may then be mounted over the standard and tube by applying equal and opposite force to the tabs 21 and 22, respectively in the plane of the tabs and perpendicular to the tube axis, which action causes enlarging of the tubular cavity formed by the wrapper thereby permitting the desired placement of the shield. Upon release of the tabs, the wrapper 28 will contract to snugly inclose the tube, the louvers 26 interlocking with the louvers 18 at the desired adjustment, so that the head portion 25 will fit across the neck of the tube so as to retain the tube axially.

Once the tube becomes heated, the mounted tube shield assembly will provide a good ground connection to the v chassis and a conductive heat path from the tube to the chassis. The interlocking louvers 18 and 26 will, of course, aid in the cooling operation by allowing upward circulation of cool air within the standard.

Ready access may be gained to the tube simply by pressing the tabs 21 and 22 in opposite directions, disengaging the mated louvers, and removing the shield; longitudinal adjustment may *be made by following the same procedure.

It will thus be seen that the design and method of operation of my tube shield offers many advantages heretofore not utilized, notably the fact that the tube shield is constructed of only two parts, preferably blanks by stamping, both being resilient to permit adaptability over a wide range, yet will contract to snugly fit each tube. In addition, the shield may be adjusted to accommodate various lengths of tubes, the louvered portions acting not only as air circulation means but as holding means to lock the clamp into position.

and upright finger portion provided with louvers, said wrapper enclosing said finger and said tube under spring action and provided with louvers mating said louvered finger to adjustably interlock said 'wrapper upon said finger, intermeshing tab ends at the free ends of said wrapper to oppose said spring action upon application of force to the ends of said tabs, and means to retain said tube axially.

2. A tube shield for supporting and locking a subrniniature tube withinits socket, comprising: a resilient bracket support and cylindrical shield member, saidsupport having a base plate and a louvered standard, said shield member having a cylindrical wrapper to enclose said louvered standard and said tube, said wrapper provided with a mated louvered portion to interlock with said louvered standard and intermeshing tab portions at the free ends thereof substantially mutually opposed in direction so as to release said wrapper from said tube by applying equal and opposite forces to the ends of said tabs, and means to retain said tube in longitudinal position within said shield.

3. A tube shield assembly comprising: a plate, aper- An additional notable feature is the fact that my shield may be removed or adtured at its lower end to receive the base of a vacuum tube, said plate being bent vertically to bear against the surface of said tube intermediate the ends thereof; louver members inclining outwardly and downwardly from the surface of said vertically bent portion, said members being vertically spaced intermediate said tube base and the top of said plate; a resilient expansible tubular shield enclosing said vertically bent portion and said tube, said shield having complemental louvers extending outwardly and downwardly therefrom for locking engagement with the edges of said first louver members, said shield having an extension at the top thereof bent laterally over said plate for retaining engagement with the top end of said tube.

4. A tu'be shield assembly comprising: a plate apertured at its lower end to receive the base of a vacuum tube, said plate being bent vertically to bear against the surface of said tube intermediate the ends thereof; stiifening ribs disposed at the opposite sides of the vertically bent portion of said plate disposed to extend longitudinally at opposite sides of said tube; louver members inclining outwardly and downwardly from the surface of said vertically bent portion, said members being vertically spaced between said ribs and intermediate said tube base and the top of said plate; a resilient, expansible tubular shield enclosing said vertically bent portion and said tube, said shield having complemental louvers extending outwardly and downwardly therefrom for locking engagement with the edges of said first louver members, said shield having an extension at the top thereof bent laterally over said plate for retaining engagement with the top end of said tube.

5. The shield assembly according to claim 4, in which said tubular shield is provided with intermeshing extensions at the vertical side edges thereof for removal and adjustment of said shield.

References Cited in the file of this patent UNITED STATES PATENTS 2,080,913 Hafecost May 18, 1937 2,499,612 Staver Mar. 7, 1950 2,611,807 Lazzery Sept. 23, 1952 2,808,576 Brown Oct. 1, 1957 OTHER REFERENCES Publication I, Sylvania Subminiature Tubes, published by Sylanvia Electric Products Inc., 1740 Broadway, New York 19, N. Y. (Pages 3 and 4 relied on.) Copy in Div. 69, Class 174-35.5. 

